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<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <!-- <form action="">
        <input type="button" value="这是一个按钮" onclick="alert('hello~~~')">
    </form> -->
    <!-- <form action="">
        姓名：<input type="text" name="name"><br>
        学号：<input type="text" name="num"><br>
        课程：<input type="text" name="course"><br>
        <input type="submit">
        <input type="reset">
        <input type="file">
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    <form action="">
        <input type="file">
    </form>
</body>
</html>